import assert from 'assert'
import math from '../../../src/defaultInstance.js'
const string = math.string

describe('string', function () {
  it('should be \'\' if called with no argument', function () {
    assert.strictEqual(string(), '')
  })

  it('should convert a boolean to a string', function () {
    assert.strictEqual(string(true), 'true')
    assert.strictEqual(string(false), 'false')
  })

  it('should convert null to a string', function () {
    assert.strictEqual(string(null), 'null')
  })

  it('should be the identity if called with a string', function () {
    assert.strictEqual(string('hello'), 'hello')
    assert.strictEqual(string(''), '')
    assert.strictEqual(string(' '), ' ')
  })

  it('should convert the elements of an array to strings', function () {
    assert.deepStrictEqual(string([[2, true], ['hi', null]]), [['2', 'true'], ['hi', 'null']])
  })

  it('should convert the elements of a matrix to strings', function () {
    assert.deepStrictEqual(string(math.matrix([[2, true], ['hi', null]])),
      math.matrix([['2', 'true'], ['hi', 'null']]))
  })

  it('should convert a number to string', function () {
    assert.strictEqual(string(1 / 8), '0.125')
    assert.strictEqual(string(2.1e-3), '0.0021')
    assert.strictEqual(string(123456789), '1.23456789e+8')
    assert.strictEqual(string(2000000), '2e+6')
  })

  it('should convert a bignumber to string', function () {
    assert.strictEqual(string(math.bignumber('2.3e+500')), '2.3e+500')
  })

  it('should convert a complex number to string', function () {
    assert.strictEqual(string(math.complex(2, 3)), '2 + 3i')
  })

  it('should convert a unit to string', function () {
    assert.strictEqual(string(math.unit('5cm')), '5 cm')
  })

  it('should throw an error if called with wrong number of arguments', function () {
    assert.throws(function () { string(1, 2) }, /TypeError: Too many arguments/)
    assert.throws(function () { string(1, 2, 3) }, /TypeError: Too many arguments/)
  })
})
